Android 多媒体拍照以及录视频

我上一篇博客写了多媒体关于音乐播放，接下来我就写一个关于自定义手机拍照和手机录视频。

一、手机拍照

1、先写一个简单的拍照布局

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:id="@+id/activity_main"
android:layout_width="match_parent" android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.example.cameravideo.MainActivity">

<SurfaceView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:id="@+id/sv_main_surface"
/>

<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:onClick="takePhoto"
android:text="拍照"
/>
</LinearLayout>

2、再写Java代码

package com.example.cameravideo;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class MainActivity extends AppCompatActivity {

private SurfaceView sv_main_surface;
private Camera camera;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

sv_main_surface = (SurfaceView) findViewById(R.id.sv_main_surface);

sv_main_surface.getHolder().addCallback(new SurfaceHolder.Callback() {
@Override
public void surfaceCreated(SurfaceHolder surfaceHolder) {
//打开照相机
camera = Camera.open();
//设置参数
Camera.Parameters parameters=camera.getParameters();

parameters.setPictureFormat(PixelFormat.JPEG);

parameters.set("jpeg-quality",85);

camera.setParameters(parameters);

//将画面展示到SurfaceView
try {
camera.setPreviewDisplay(sv_main_surface.getHolder());
} catch (IOException e) {
e.printStackTrace();
}

//开启预览效果
camera.startPreview();
}

@Override
public void surfaceChanged(SurfaceHolder surfaceHolder, int i, int i1, int i2) {

}

@Override
public void surfaceDestroyed(SurfaceHolder surfaceHolder) {
if(camera!=null){
camera.stopPreview();
camera.release();
camera=null;
}
}
});
}

public void takePhoto(View view){
camera.takePicture(null, null, new Camera.PictureCallback() {
@Override
public void onPictureTaken(byte[] bytes, Camera camera) {
//技术：图片压缩技术
Bitmap bitmap= BitmapFactory.decodeByteArray(bytes,0,bytes.length);

try {
FileOutputStream fos=new FileOutputStream("/DCIM/Camera/G150820_"+System.currentTimeMillis()+".png");
bitmap.compress(Bitmap.CompressFormat.PNG,85,fos);
camera.stopPreview();
camera.startPreview();
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
});
}
}

二、手机录视频

1、据上，写一个简单的布局

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_media_recorder"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"

4000
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:orientation="vertical"
tools:context="com.example.cameravideo.MediaRecorderActivity">

<SurfaceView
android:layout_width="match_parent"
android:layout_height="350dp"
android:id="@+id/sv_recorder_surface"
/>

<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="开始"
android:onClick="start"
/>

<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="结束"
android:onClick="stop"
/>

</LinearLayout>

2、写Java代码

package com.example.cameravideo;
import android.media.MediaRecorder;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.SurfaceView;
import android.view.View;

import java.io.IOException;

public class MediaRecorderActivity extends AppCompatActivity {

private SurfaceView sv_recorder_surface;
private MediaRecorder mediaRecorder;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_media_recorder);
sv_recorder_surface = (SurfaceView) findViewById(R.id.sv_recorder_surface);
//实例化媒体录制器
mediaRecorder = new MediaRecorder();
}

public void start(View view){
mediaRecorder.reset();;
//从照相机采集视频mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);

//设置格式
mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);

////设置视频编码方式
mediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H263);
mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);

//设置保存路径
mediaRecorder.setOutputFile("/mnt/sdcard/G150820_"+System.currentTimeMillis()+".mp4");

mediaRecorder.setPreviewDisplay(sv_recorder_surface.getHolder().getSurface());

try {
mediaRecorder.prepare();
mediaRecorder.start();
} catch (IOException e) {
e.printStackTrace();
}
}

public void stop(View view){

if(mediaRecorder!=null){
mediaRecorder.stop();
mediaRecorder.release();
mediaRecorder=null;
}

}
}

两者最重要的是：权限

<!-- 打开照相机的权限 -->
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />